The current structure of a projector includes an illumination system, a light valve and a projection lens. Specifically, the illumination system is for providing the illumination light beam; the light valve is for converting the illumination light beam into an image light beam; and the projection lens is for projecting the image light beam onto a screen, thereby forming images on the screen. Based on the types of light valve, projectors can be divided to digital light processing (DLP) projector, liquid crystal digital projector and liquid crystal on silicon (LcoS) projector.
However, the illumination system of the existing lighting system projectors must use a lot of optical components, which may lead to problems such as such as high cost, large component size and loud noise. Thus, it is quite import for the person in the art to solve the aforementioned problems.
The information disclosed in this “BACKGROUND OF THE INVENTION” section is only for enhancement understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Furthermore, the information disclosed in this “BACKGROUND OF THE INVENTION” section does not mean that one or more problems to be solved by one or more embodiments of the invention were acknowledged by a person of ordinary skill in the art.